A blog about some of the Antarctica Weddell seal population study field research work and outreach efforts during the Weddell seal pupping season in the Erebus Bay region of Antarctica's Ross Sea. Weddell seal images and recordings obtained under NMFS Permit Nos. 1032-1917, 17236, and 21158. More information at http://WeddellSealScience.com

October 2014

28 October 2014

One of the big questions I had for the Weddell Project 2014 Antarctic field team was whether the very old Weddell mom with the study record number of pups had lived to return again to the Erebus Bay Study area, and whether she had a new pup this year. Per Weddell population study lead scientist Jay Rotella, the great news is that she has lived through another winter and returned--and she has given birth to her 22nd pup! This is a new Weddell population study record.

Photo by Jay Rotella of the very rare old huge mom with her very recently born tiny pup.

This is a very rare old Weddell mom. According to lead project scientist Jay Rotella, who is currently working in the field as part of the 2014 Antarctica field team, what is so remarkable about this Weddell mom is that she has had 22 total pups so far. She produced pups at ages 8, 9, 10, (3 in a row then 1 year off), 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, (16 in a row then 2 years off) 30, 31, and 32 (3 in a row for the 3 most recent years). Weddell seal moms live an average of 15 years, and usually have around 2 pups every 3 years, so this long life and frequency of pupping is very unusual.

Photo by Jay Rotella of this year's view of part of the Hutton Cliffs Weddell seal colony on smooth 1st year ice.

All of the pups of SPENO 5970, as she's known in the database, were born at Hutton Cliffs. For the past several years Hutton Cliffs has been a rugged area with jumbled multi-year ice, hummocks, and rough sastrugi. This year the ice is smooth 1st year ice; and much of the seal colony can be seen for some distance on the flat terrain.

This rare old mom was born in 1983 at an area called the North Base of the Erebus Glacier Tongue. This area is relatively close to the Hutton Cliffs pupping colony, where all of this Weddell mom's 22 pups have been born over her reproductive life to date.

Close-up of the old mom and her 22nd pup this 2014 season, photo by Bill Link, NMFS Permit 17236.

Working with the extensive database, lead population study scientist Jay Rotella was able to determine that of SPENO 5970's first 21 pups, 11 were females and 10 were males. "Of those offspring, 2 sons and 2 daughters have been seen again, which is right in line with what we'd expect based on other analyses indicating that roughly 20% of the seals make it to adulthood." Her new pup is a female.

Another portrait shot of the old mom and her 22nd pup this 2014 season, photo by Bill Link, NMFS Permit 17236.

Of SPENO 5970's surviving offspring, two daughters have returned to the pupping colonies to give birth themselves. One of those daughters is 23 years old and has produced 13 pups so far. One of that daughter's pups--a granddaughter of SPENO 5970--has gone on to have 5 pups herself.

Photo by lead scientist Bob Garrott of old mom in 2013 with her 21st pup showing the rugged terrain of Hutton Cliffs last year.

According to the database, Rotella notes that the old Weddell mom has at least 14 grandpups and 5 great grand-pups. We look forward to more photos of SPENO 5970 from the team this year as her 22nd pup gets bigger and bigger!

Photo by 2014 field team leader Terrill Paterson taken last year of old mom's 21st pup growing larger.

25 October 2014

This is the 2nd half of Part 1 of our new series, "How Do Weddell Moms Matter? Part 1: Cohort Effects and Conditions Before Birth." (Read 1st half of Part 1 here.) The 2nd half of Part 1 continues...

Project scientists suspect (but don’t really know for certain) that a female starts to regain body mass as soon as she weans her pup. But there is a lot of uncertainty about the dynamics of Weddell mom mass gain—whether it occurs quickly over a month or two, or gradually over many months, and whether the summer is when most mass is gained, or the winter. Or perhaps both summer and winter seasons contribute equally.

Delayed implantation of the fertilized egg in the mother's womb is exclusively a summer phenomenon, while overall body mass gain by Weddell moms could be a result of summer or winter conditions, or a combination of conditions spanning both seasons. (Please see the previous post of the 1st section of this writing for more information on Weddell seal females being "delayed implanters.")

Weddell pup nursing on the sea ice with a nearby Weddell colony in the background.

One of the main environmental factors affecting the amount of food available for the Weddell females during winter is the amount of sea ice extent. Scientists have hypothesized that the Ross Sea marine ecosystem is strongly structured from the top down, indicating that high level predators such as Weddell seals have a strong influence on the overall ecosystem. There is thought to be substantial predator competition by minke whales, emperor and Adélie penguins, killer whales (orca), snow petrels, and Antarctic toothfish for food resources such as Antarctic silverfish, a major prey of Weddell seals.

Increased sea ice extent limits access to food resources by competing predators such as whales and birds; and the amount of food Weddell moms can obtain during the winter when their unborn pups are developing in utero may be greater. The more mass the moms can put on, the bigger the pups are likely to be when they’re born the following spring, and the bigger the moms. Bigger moms can transfer more energy and mass to their nursing pups after birth. Bigger pups have a greater likelihood of surviving to reproductive age and recruiting—returning to a pupping colony and giving birth to pups, themselves. Project scientists have concluded that annual variation in food resources available to pregnant Weddell females was likely the driver of variation in recruitment probability among cohorts (Garrott et al. 2012).

One of the most significant findings described in Garrott et al. 2012 is that bigger cohorts do better. So when conditions are such that more females do produce pups, those bigger cohorts have a greater proportion of female pups that go on to become mothers, themselves. It will be particularly interesting to see how the most recent record-breaking or near-record pupping seasons—cohorts—fare in the next several years.

Photo by Bill Link of a mom and pup at Turks Head Weddell seal colony, NMFS Permit 17236.

So from the beginning, Weddell moms and the varying environmental conditions they encounter make a difference in whether the fertilized eggs implant, how much nutrition the unborn pups gets while in utero, how much energy and mass is available to transfer to the pups after birth while nursing and, thus, the likelihood of whether the pups in the particular annual pup cohort recruit—survive to return to the pupping colonies and give birth to pups of their own.

Cohort, here, refers to all of the Weddell pups born in the Erebus Bay study area in one pupping season, which occurs starting in mid-October and continues until late November each year. What makes this discovery especially interesting is that the scientists were able to take 30 year’s worth of data from 4178 tagged female Weddell pups born into 20 different annual cohorts, and 30 years of mark-resight observation data to discover that there are large differences in the proportion of each annual cohort that survives to return to the pupping colonies and produce a pup within 10 years of their birth. Because Weddell seal females have strong birth area fidelity (natal philopatry) and return to the area of their birth to give birth to their own pups, and it has been found that 93% of breeding females produce their first offspring by age 10 (Hadley et al. 2006), it is likely that Weddell females that have not recruited into the Erebus Bay breeding population within 10 years have died.

Two Weddell seals encounter each other under the sea ice in this video clip by Henry Kaiser, 2009.

The study data strongly supports an association between “cohort recruitment probability” and the regional extent of sea ice experienced by the mother during the winter the pup was in utero (Garrott et al. 2012). Cohort recruitment probability refers to the likelihood of female Weddell seal pups surviving to adulthood and returning to the pupping colonies as adults to give birth to pups of their own.

There are probably many reasons why there are differences in the proportion of females of a cohort that return to reproduce, but project scientists suspect it all starts with whether the fertilized egg of a Weddell seal female implants in her uterus, which may be influenced by the level of nutrition the mom experiences during the austral summer. Another reason would be the level of nutrition the mom experiences in the austral winter as the pup is developing in utero, and the mom is continuing to gain mass.

Two Weddell seals share a breathing crack in the sea ice.

Weddell seal females are “delayed implanters”. They usually mate underwater in early December at the end of the 30 to 45 day nursing period in the late austral spring or early summer. However, the fertilized egg does not implant in the mother’s uterus for a month or two after mating. Although we do not have physiological data, project scientists think that the more food resources available to the Weddell females in a particular austral summer season, the more likely the fertilized egg, or blastocyst, will implant in the mom’s uterus and the embryo will begin to develop and grow.

Thus far, we have tagged a few dozen pups and are completely caught up in our study area. We were hutbound for a day and a half due to a pretty awesome storm (during which Michael [Yarnall] and I had to drill emergency anchors on the outhouse to keep it from blowing away), but spent a very long day today getting caught up in the Dellbridge Islands, and at Hutton and Turtle Rock. I have so far coerced seven moms to get on the weigh sled (we have the associated photogrammetry projects) and it looks like we may be able to get three more tomorrow. I currently have a nice assortment of ages for our weighers, with a few 5 to 10 years olds, and a few 20 plus. The driving conditions are such that we can get the [weigh] sled all the way to Turtle Rock (it just costs me and one other crew member a bit of time). We are also on schedule with our temperature tagging effort; I deployed the fifteenth tag this afternoon on a very young pup at Turtle Rock.

Most remarkable for me, the sea ice at Hutton is spectacularly different from last year. Gone are all of the pressure ridges and multiyear sea ice hummocks. It is flat, first year ice all the way to Hutton and a great deal of the way to South Base. The crew worked a hard afternoon getting caught up at Hutton, and it was a bit of a relief that they did not have to contend with ice-related hazards as they are trying to learn and keep up with all the different goals and projects for B009.

18 October 2014

Here is the full 12 minute version of the "Being Different If You're A Weddell Seal in Antarctica" project short film:

This film was a 2014 Finalist in the Cannes Film Festival American Pavilion of Emerging Filmmakers and an Official Selection of the Cannes Short Film Corner, an Official Selection at the New Media Film Festival in Los Angeles, an Official Selection of the Beneath the Waves Film Festival, an Official Selection of the recent San Diego UnderSea Film Exhibition (a 5 minute version), and a Finalist at the BLUE Ocean Film Festival & Conservation summit next month.

Currently, I am working with the Weddell population project scientists on our new short film, "Do Mom's Matter?" (fondly referred to as "Who's Your Mama?"). I will be posting on this blog during the current pupping season on topics relating to how Weddell moms matter to their pups' likelihood of survival to adulthood and future reproduction.

17 October 2014

Working in Antarctica brings with it a host of new experiences, thoughts, and sensations. Once experienced, it's never forgotten. And you can find yourself wanting to return over and over again. What is especially fascinating are the first impressions of team members as a new season begins. What follows are the writings of some of the 2014 Weddell seal field team members soon after arriving for the upcoming Weddell pupping season:

From the 2014 Field Research Crew:

When we are out on the sea ice, seals aren’t the only animals that we see. We also encounter birds, such as penguins. The other day, we saw a group of ~30 emperor penguins who were just as curious about us as we were about them. We paused to watch the penguins as they, in turn, studied us then continued on with our work.

There have been so many moments while down in Antarctica that become stuck, immortalized in the lexicon of our memories that it's difficult to think of just one. The parting of the clouds allowing rays of sun to illuminate a grounded iceberg, penguins creating a curious traffic jam, Mt. Erebus letting off steam, seals dotting the horizon, soft serve ice cream named 'frosty boy' being aggressively and faithfully enjoyed in negative temperatures... there are so many memories that will stay with me for the rest of my life... but perhaps the one so far that keeps replaying in my mind, that I see when I close my eyes, would be the memory of looking into a Weddell seal's eyes for the first time. The seal was on her stomach and had arched her back and rolled her head towards me to get a better look as I approached. Her body was in such a position that she couldn't fully turn to face me, rather she tilted her head back and looked up at me through the tops of her eyes. Her huge brown eyes lightly rimmed with red - a color that instantly made me think of my time spent in the heavily chlorinated swimming pools back home as a kid - looked up at me with what I couldn't help but recognize as absolute serenity and calm and a disconnected mild curiosity.

I know it's not the role of an objective biologist to entertain such thoughts but I couldn't help but see these qualities in the animals eyes when she looked at me. Those big beautiful brown eyes had a story of which I was there to learn only a tiny fraction. Those eyes have seen things I can't imagine and will continue to see and observe a world I can only visit in and truthfully only see with my imagination. I feel honored to have met the gaze of those eyes and to have been in their focus if only for a few seconds or so.

There have been many exciting aspects to our first week or so, in McMurdo. Our first day out on the sea ice we had the opportunity to visit Scott's Hut at Cape Evans that was used both by Scott and later Shackleton's men during their respective expeditions. It was so incredible to see the gear and living conditions that those men survived in. While, it was so inspiring to see a piece of human history in Antarctica, it has been just as inspiring to see the animals that thrive in this environment. The vocalizations of the Weddell seals as they move under the ice seems so eerie. Watching mom and pup lounge on the ice, with little regard for the frigid temperatures is a testament to how well adapted these animals are to their environment. The curiosity of the Emperor penguins as they approached us on the road, more than 8 kilometers from where they live was a sight I will never forget! I'm so excited to get to know this wild land and the animals that inhabit it a little bit better.

Flying past Terra Nova Bay and over the Drygalski Tongue on a clear day as the view from high up in the Airbus complemented the lower view from the helo a few years ago very well. Getting camp pulled so that we can really get serious about starting the season. Interacting with FSTP, BFC, Carps, etc. and seeing how excited all the science support folks are about helping B-009 have a successful season.

Coming to Antarctica is what some people call a dream and for most it is. Actually being here and experiencing this place can feel like a dream with many surreal events compiling on top of each other with little time to actually process the moment before the next comes rushing in. The moments that stand out from the rest would be encountering 32 Emperor Penguins only being an arm’s reach away and tagging my first Weddell seal pup. Two events that seemed like a dream but were real.

Thank you to the 2014 Field Research Team Members for letting us in on some of their impressions of Antarctica shortly after arrival!

Bob is a Professor in the Ecology Department at Montana State University and director of the MSU Fish and Wildlife Ecology and Management Program. His work focuses on the abiotic and biotic ecological processes that influence mammalian populations and communities, in both terrestrial and marine ecosystems, and contributing to basic science as well as applied wildlife management and conservation through collaborations with state and federal natural resource agencies. Bob received his PhD in Wildlife Conservation, University of Minnesota, 1990. More on Bob.

Dr. Donald Siniff, Co-Principal Investigator

Don is a Professor Emeritus in the Department of Ecology, Evolution, and Behavior at the University of Minnesota where his work has centered on the population dynamics of large mammals. Don's research has focused on the population characteristics of three species of Antarctic seals, concentrating on a long-term program on Weddell seals with shorter term studies on the crabeater and leopard seals of the Antarctic. He has also studied sea otters in Alaska and California since 1975. Don received his PhD from the University of Minnesota, 1967. More on Don.

Terrill Paterson, Weddell seal research field team leader

Terrill is a PhD student at Montana State University, and has a background in science education. He began working on the Weddell seal project in 2013. Terrill is the 2014 Field Research Team leader. He is also an accomplished field photographer and videographer.

Michael Yarnall, Weddell seal research field team

Michael graduated in 2011 from Montana State University with a double option in Ecology & Evolution and Fish and Wildlife Management. This is his third season working for the Weddell Seal Project. In addition to previous work on the Ice, Michael has worked as a wildlife technician on a diverse range of projects and species, including goshawks, sage grouse, and trout. Most recently he worked for the US Forest Service developing multiple habitat improvement projects to benefit a variety of species including mule deer, mountain goats, upland game birds, and neotropical migrants.

Kirstie Yeager, Weddell seal research field team

This is Kirstie’s second year working on the Weddell Seal Project with Montana State University. Prior to coming to McMurdo, Kirstie received a BA in Biology from the University of Hawai’i at Manoa and has worked as a Bio-Science Field Technician on a variety of projects including: the Colorado River Fisheries Project with the US Fish and Wildlife Service; a variety of terrestrial mammal projects with Colorado Parks and Wildlife; the seabird component of the Long Term Ecological Research (LTER) project at Palmer Station, Antarctica; the Hawaiian Monk Seal Project in the Northwestern Hawaiian Islands; and the Steller Sea Lion observation program at Ugamak Island, Alaska. Kirstie is currently a graduate student in the Cooperative Fish and Wildlife Research Unit at Colorado State University where she is pursuing a Master’s Degree in Ecology and Fish & Wildlife Studies.

Kaitlin Macdonald, Weddell seal research field team

Kaitlin Macdonald has worked on Montana State University research projects since 2012. The 2014 Weddell seal project season is Kaitlin’s first on the project. Kaitlin has done field work with mountain ungulates and small mammals. She most recently worked as a field technician studying dispersal of Hoary marmots in northwest Montana. She holds a B.A. in Environmental Studies and a B.S. in Economics from Montana State University.

Jonathan Rees, Weddell seal research field team

Jonathan Rees is originally from Yardley Pennsylvania and a graduate of the University of the Arts with a Bachelors of Music in Jazz Studies and a Master of Arts in Teaching in Music Education. He taught for four years in the Pennsylvania Public School system and performs professionally on national and international stages touring with ensembles such as The Glenn Miller Orchestra, The Joshua Stamper Quartet, and the Philadelphia Boys Choir. For the past five years Mr. Rees has worked as a Park Ranger and EMT with the National Park Service and most recently as a research assistant with MSU on various ecology and range science projects. Mr. Rees is a constant adventurer and is thrilled to be studying seals on one of the most remote and beautiful places on earth.

Eric Boyd, Weddell seal research field team

Eric Boyd recently received his BS in Fish & Wildlife Management from Montana State University. He has worked as a field technician on a previous large carnivore population study involving Grizzly Bears in the Cabinet-Yaak Ecosystem. His backcountry experience is extensive and has mountain travel and safety, first responder, and swiftwater rescue knowledge. Eric began working on the Weddell Seal Project in 2014.

Mary Lynn Price, Weddell seal project video and digital specialist

Mary Lynn has been working with the Weddell seal project since 2010 as a public outreach and informal science education video and multimedia producer. Her digital production background includes short format videos for news and science organizations, educational institutions, film festivals, art galleries, and internet projects. She developed and maintains the Weddell Seal Science multimedia web portal, and produces short videos for public outreach and informal science education. She has deployed to Antarctica to produce videos since 2008 when she participated in an International Polar Year project producing short video portraits on woman working in Antarctica. Her recent work also involves editing 4K stereoscopic 3D underwater footage for natural history cinematographers. More on Mary Lynn.

15 October 2014

The 2014 sea ice camp has now been set for the Weddell pupping season, and is located at Big Razorback Island, one the volcanic Dellbridge Islands in Erebus Bay. The sea ice camp is located near the southernmost active volcano on Earth, Mt. Erebus. This frame comes from a wonderful satellite imaging flyover created by NASA/Goddard Space Flight Center Scientific Visualization Studio; LIMA Data provided by: Patricia Vornberger (SAIC); LIMA data produced by U.S. Geological Survey (USGS), the British Antarctic Survey (BAS) and NASA.

What follows is a report from field crew leader and Weddell project PhD Student, Terrill Paterson:

Good morning, all!

Seal camp has officially been put it, and B-009 is ready to get to work! Weather delays have caused quite the back up of teams and personnel trying to get to the ice; many of our friends have been delayed over a week. We were lucky and made it to the ice on a clear day before a week of snow and storms. A wide variety of people at McMurdo helped us tremendously as we geared up for our season. Ten days of preparation finally paid off as we had camp pulled out to Big Razorback yesterday, and the carpenters and electricians powered and heated our huts today.

Whilst in McMurdo, we managed to get out several times as conditions permitted. We spend a few days flagging roads from Big Razorback to Turk’s Head and Tryggve Point, and again from the Cape Evans road to Turtle Rock. The conditions here are very nice for our work. Last summer, much of the multiyear ice that causes us such headaches ‘blew out’ of places such as North Base, Hutton and South Base. The resulting sea ice is very smooth and apparently quite stable. As a bit of a treat, several large icebergs have been grounded near Cape Evans a few miles north of camp. These are large chunks of ice which broke off the Ross Ice Shelf and drifted into Erebus Bay. They are very beautiful, and we will send pictures soon as we investigate them for safety and survey reasons.

The sun behind an island in Erebus Bay, photo by Terrill Paterson, 2014.

We tagged our first pup on October 5th at Turtle Rock, a pup our support staff thinks may have been born in late September, a very early birth day! There are few pups just yet. We have only found a few at Tent Island, including a newborn pup that was still wet and an unfrozen placenta. We know his mom pretty well and plan on finding out as much information as we can about his swimming habits and changes in mass as he nurses from Mom.

Research field team member Michael Yarnall tagging a new seal pup in this photo by Terrill Paterson, 2014.

Our upcoming week (working from camp) is very exciting. We have a helicopter flight scheduled for Monday morning (Sunday on US time). I am taking Michael (an excellent returning field tech with experience on many projects, responsible for the mass database) and Kirstie (an outstanding returning field tech and a woman with a great deal of experience from the Monk seal project in Hawaii, responsible for the temperature tag database) to explore our study area, looking for cracks and seals. They will be responsible for leading teams in the next week (as experienced and returning technicians) and it would serve us all well to get a broad perspective on the study area. Later that day (and probably a couple of ensuing days), we will press into the Hutton cliffs area, one of the most beautiful places in our study area. Our objective is to get out there to tag and weigh pups! I am excited to learn how to weigh moms using a specialized sled and a whole lot of patience. It is a lot different than running cattle through a chute, which is what I spent time doing as a kid.

02 October 2014

The Weddell seal population study 2014 field research team is now in Antarctica, and making preparations to set up the remote sea ice camp from which they'll be working this Weddell pupping season. The team this season includes team leader and PhD student Terrill Paterson, returning field team members Michael Yarnall and Kristie Yeager, and new field team members Kaitlin Macdonald, Jon Reese, and Eric Boyd.

After boarding a specialized jet for the five hour trip South to the ice, the team made the best of the flight by catching up on sleep, and enjoying the view of their approach to the Antarctic Ice.

Once in Antarctica, the team was briefed at the National Science Foundation chalet, and issued dorm rooms at McMurdo Station where they will stay while preparations are made for setting up the seasonal remote sea ice camp where they will live and work during the entire Weddell seal pupping season. The team will also go through a number of training courses while at McMurdo to better prepare them for their work on the sea ice.

Photos by Terrill Paterson, PhD student and field team leader.

In our upcoming posts we will further introduce the members of the 2014 field research team, as well as introduce our theme for the upcoming Weddell pupping season, "Do Moms Matter?"